(1) Field of the Invention
This invention relates to hot metal runners as used in the metal producing industry for delivering molten metal from a source to a remote point.
(2) Description of the Prior Art:
Runners for handling hot metal are disclosed in U.S. Pat. No. 2,409,741 and such runners generally comprised metal shapes with clay liners as will be understood by those skilled in the art.
U.S. Pat. No. 3,174,739 relates to a nose for a furnace tap hole runner and wherein the nose, like the runners with which it is used, comprises a metal shape having a refractory lining in the nature of a permanent monolithic layer.
U.S. Pat. No. 3,365,187 shows a runner system for a blast furnace.
The runners in general use at the time of the patent's filing comprised clay shapes, some of which were carried in metal shells.
U.S. Pat. No. 3,480,125 shows a fibrous insulating material and a channel which is noted as being used to convey molten metal in a foundry and U.S. Pat. No. 3,600,480 relates to a process of repairing runners and describes the runner itself as being made of refractory material with an inside lining composed of clay and carbon.
The prior art runners were primarily refractory articles, sometimes with a metal jacket and sometimes with a lining formed of a refractory material and an additive. They were all designed and formed of materials the would have the longest possible life and most of them were capable of being repaired as disclosed in the prior art U.S. Pat. No. 3,600,480, mentioned hereinabove.